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FXUS06 KWBC 311901
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON AUGUST 31 2015

6-10 DAY OUTLOOK FOR SEP 06 - 10 2015

TODAY`S MODEL SOLUTIONS ARE IN FAIR AGREEMENT ON THE PREDICTED 500-HPA FLOW
PATTERN OVER NORTH AMERICA AND VICINITY. THE ENSEMBLE MEAN SOLUTIONS FROM THE
GFS, ECMWF, AND CANADIAN FORECAST TROUGHS OVER THE BERING SEA AND OVER THE
NORTHWESTERN CONUS. RIDGING IS PREDICTED FOR THE NORTHEASTERN AND SOUTH-CENTRAL
CONUS. A SHORTWAVE TROUGH IS FORECAST BY THE ECMWF-BASED MODELS AS WELL AS
TODAY`S DETERMINISTIC GFS RUNS OVER THE SOUTHEASTERN CONUS. TODAY`S 0Z ECMWF
ENSEMBLE MEAN IS THE LARGEST COMPONENT OF THE OFFICIAL 500-HPA MANUAL HEIGHT
BLEND DUE, IN PART, TO CONSIDERATIONS OF RECENT SKILL. HOWEVER, SIGNIFICANT
CONTRIBUTIONS FROM THE GFS AND CANADIAN ARE ALSO PRESENT. THE RESULTANT HEIGHT
BLEND DEPICTS ABOVE NORMAL 500-HPA HEIGHTS OVER THE NORTHEASTERN CONUS AND
ALASKA AND BELOW NORMAL HEIGHTS FOR PARTS OF FLORIDA. ELSEWHERE, NEAR NORMAL
HEIGHTS ARE PREDICTED.

BELOW NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE ROCKIES IN ASSOCIATION
WITH A TROUGH PREDICTED OVER THE NORTHWESTERN CONUS. ABOVE NORMAL TEMPERATURES
ARE FAVORED AHEAD OF THIS TROUGH OVER THE EASTERN AND SOUTH-CENTRAL CONUS.
ENHANCED PROBABILITIES OF ABOVE NORMAL TEMPERATURES ARE ALSO INDICATED FOR
ALASKA AHEAD OF THE TROUGH PREDICTED OVER THE BERING SEA. PROBABILITIES OF
ABOVE NORMAL TEMPERATURES ARE ENHANCED ALONG THE WEST COAST OF THE CONUS DUE IN
PART TO ABOVE NORMAL SSTS CURRENTLY OBSERVED IN ADJACENT WATERS.

THERE ARE ENHANCED PROBABILITIES OF ABOVE MEDIAN PRECIPITATION FOR MUCH OF THE
NORTHERN AND CENTRAL PLAINS AHEAD OF THE TROUGH PREDICTED OVER THE NORTHWESTERN
CONUS. PREDICTIONS FROM THE GFS AND ECMWF ENSEMBLE MEMBERS ALSO FAVOR ABOVE
MEDIAN PRECIPITATION FOR PARTS OF THE SOUTHWESTERN CONUS. FARTHER TO THE EAST,
BELOW MEDIAN PRECIPITATION IS SLIGHTLY FAVORED FOR PARTS OF SOUTHERN TEXAS
UNDERNEATH FORECAST RIDGING. THERE ARE ENHANCED PROBABILITIES OF BELOW MEDIAN
PRECIPITATION FOR THE NORTHWESTERN CONUS CONSISTENT WITH GEFS REFORECAST
GUIDANCE. CONVERSELY, ABOVE MEDIAN PRECIPITATION IS FAVORED FOR MUCH OF THE
SOUTHEASTERN CONUS DUE TO A FORECAST SHORTWAVE TROUGH IN THE VICINITY. ENHANCED
PROBABILITIES OF ABOVE MEDIAN PRECIPITATION ARE ALSO INDICATED FOR SOUTHWESTERN
ALASKA AHEAD OF A TROUGH PREDICTED OF THE BERING SEA. BELOW MEDIAN
PRECIPITATION IS FAVORED FARTHER AWAY FROM THE TROUGH AXIS FOR NORTHEASTERN
ALASKA.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 5% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 10% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 10%
OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 15% OF TODAY`S OPERATIONAL 6Z
GFS CENTERED ON DAY 8, 20% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY
8, 10% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, 5% OF
TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, 5% OF YESTERDAY`S OPERATIONAL
12Z ECMWF CENTERED ON DAY 7, 10% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED
ON DAY 8, AND 10% OF YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 7


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, DUE TO
FAIR MODEL AGREEMENT.

8-14 DAY OUTLOOK FOR SEP 08 - 14 2015

TODAY`S ENSEMBLE MEAN AND DETERMINISTIC SOLUTIONS GENERALLY FORECAST MOSTLY
ZONAL FLOW ACROSS MUCH OF THE NORTHERN TIER OF THE CONUS DURING THE WEEK TWO
PERIOD. FARTHER TO THE SOUTH, RIDGING IS FORECAST OVER PARTS OF THE SOUTHERN
PLAINS. ENSEMBLE SPREAD IS HIGH ACROSS MOST OF THE CONUS INDICATING LARGE
DISAGREEMENTS AMONG THE COMPONENT ENSEMBLE MEMBERS ON THE DETAILS OF INDIVIDUAL
SHORTWAVE FEATURES WITHIN THE LARGE SCALE PATTERN. AGREEMENT IS SOMEWHAT BETTER
OVER ALASKA, AS MOST MODEL SOLUTIONS AGREE IN FORECASTING A TROUGH NEAR THE
WESTERN PART OF THE STATE. DUE TO MODEL SPREAD AND UNCERTAINTY, TODAY`S WEEK
TWO MANUAL HEIGHT BLEND CONSISTS PRIMARILY OF THE ENSEMBLE MEAN SOLUTIONS.

BELOW NORMAL TEMPERATURES ARE FAVORED FOR PARTS OF THE NORTH CENTRAL CONUS
CONSISTENT WITH GEFS REFORECAST GUIDANCE. CONVERSELY, GEFS REFORECAST GUIDANCE
AS WELL AS BIAS CORRECTED TEMPERATURES FROM THE ECMWF ENSEMBLE MEMBERS FAVOR
ABOVE NORMAL TEMPERATURE FOR THE EAST AND WEST COASTS AS WELL AS THE SOUTHERN
TIER OF THE CONUS. ABOVE NORMAL TEMPERATURES ARE ALSO FAVORED FOR MOST OF
ALASKA AHEAD OF A TROUGH PREDICTED OVER THE BERING SEA.

FORECASTS FROM THE GFS AND ECMWF ENSEMBLE MEMBERS FAVOR ABOVE MEDIAN
PRECIPITATION FOR MUCH OF THE EASTERN HALF OF THE CONUS AND PARTS OF THE
SOUTHWEST. CONVERSELY, NEAR TO BELOW MEDIAN PRECIPITATION IS FAVORED FOR
SOUTHERN TEXAS UNDERNEATH PREDICTED RIDGING. THERE ARE ENHANCED PROBABILITIES
OF ABOVE MEDIAN PRECIPITATION FOR MUCH OF ALASKA IN ASSOCIATION WITH THE TROUGH
PREDICTED OVER THE BERING SEA. BELOW NORMAL PRECIPITATION IS FAVORED FOR THE
NORTHWESTERN CONUS CONSISTENT WITH GEFS REFORECAST GUIDANCE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 5% OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 11, 10% OF TODAY`S
OPERATIONAL 6Z GFS CENTERED ON DAY 11, 20% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, 15% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 10, 5% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 5% OF
YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO LARGE MODEL SPREAD AND UNCERTAINTY.

FORECASTER: SCOTT HANDEL

NOTES:


AUTOMATED FORECASTS ARE ISSUED ON SATURDAY AND SUNDAY. OCCASIONALLY MANUAL
INTERVENTION IS NECESSARY TO ADDRESS QUALITY CONTROL AND CONSISTENCY ISSUES.
IN THESE CASES, FORECASTS ARE MANUALLY DRAWN BUT A FULL DISCUSSION IS NOT
ISSUED.

THE NOTATION FOR THE CATEGORICAL FORECAST INDICATED ON THE MAPS IS
THE SAME AS THAT IN THE TABLES: A-ABOVE   N-NEAR NORMAL   B-BELOW

THE TEMPERATURE MAP SHOWS REGIONS WITH > 33% CHANCE OF BEING WARMER
(ORANGE, "A"), COLDER (BLUE, "B"), OR CLOSE TO (UNSHADED, "N")
HISTORICAL AVERAGE VALUES FOR THE CALENDAR PERIOD OF THE FORECAST
(DASHES, "F").  LABELS ON THE SHADED LINES GIVE THE PROBABILITY
(> 33%) OF THE MORE LIKELY CATEGORY (B OR A).  PROBABILITY OF N IS
ALWAYS < 40%.

THE PRECIPITATION MAP SHOWS REGIONS WITH > 33% CHANCE OF BEING
WETTER (GREEN, "A"), DRIER (TAN, "B"), OR CLOSE TO (UNSHADED, "N")
HISTORICAL MEDIAN VALUES FOR THE CALENDAR PERIOD OF THE FORECAST
(DASHES, "INCHES").  LABELS ON THE SHADED LINES GIVE THE PROBABILITY
(> 33%) OF THE MORE LIKELY CATEGORY (B OR A).  PROBABILITY OF N IS
ALWAYS < 40%.

IN THE SOUTHWEST AND OTHER CLIMATOLOGICALLY DRY REGIONS - THERE WILL
BE A GREATER THAN 33.3% CHANCE OF NO PRECIPITATION AND OCCASIONALLY
EVEN A NORMAL (I.E. MEDIAN) VALUE OF ZERO - ESPECIALLY DURING THE DRY
SEASONS.  IN SUCH CASES A FORECAST OF NEAR NORMAL IS EFFECTIVELY A
FORECAST OF LITTLE OR NO PRECIPITATION.

THE CLIMATE PREDICTION CENTER USES 1981-2010 BASE PERIOD MEANS FOR
TEMPERATURE...PRECIPITATION...AND 500-HPA HEIGHTS AS REFERENCE IN
THE CLIMATE OUTLOOKS.

THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON
SEPTEMBER 17

ANALOGS TO THE 5 DAY MEAN OBSERVED PATTERN CENTERED 3 DAYS AGO (D-3)
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE
INCLUDE THE 5 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
19520905 - 19690811 - 20000906 - 19830906 - 19600901


ANALOGS TO THE 7 DAY MEAN OBSERVED PATTERN CENTERED 4 DAYS AGO (D-4)
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE
INCLUDE THE 7 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
19600901 - 19690810 - 19520822 - 19830905 - 19690815


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 06 - 10 2015

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  N    B     OREGON      N    B     NRN CALIF   A    N
SRN CALIF   A    N     IDAHO       B    B     NEVADA      N    B
W MONTANA   B    N     E MONTANA   B    A     WYOMING     B    N
UTAH        B    N     ARIZONA     N    A     COLORADO    B    A
NEW MEXICO  N    A     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    N    A     KANSAS      N    A     OKLAHOMA    A    A
N TEXAS     A    N     S TEXAS     A    N     W TEXAS     A    A
MINNESOTA   A    A     IOWA        A    A     MISSOURI    A    A
ARKANSAS    A    A     LOUISIANA   A    A     WISCONSIN   A    A
ILLINOIS    A    A     MISSISSIPPI A    A     MICHIGAN    A    A
INDIANA     A    A     OHIO        A    A     KENTUCKY    A    A
TENNESSEE   A    A     ALABAMA     A    A     NEW YORK    A    N
VERMONT     A    N     NEW HAMP    A    N     MAINE       A    N
MASS        A    N     CONN        A    N     RHODE IS    A    N
PENN        A    N     NEW JERSEY  A    N     W VIRGINIA  A    N
MARYLAND    A    N     DELAWARE    A    N     VIRGINIA    A    N
N CAROLINA  A    N     S CAROLINA  A    A     GEORGIA     A    A
FL PNHDL    A    A     FL PENIN    A    A     AK N SLOPE  A    B
AK ALEUTIAN A    A     AK WESTERN  A    N     AK INT BSN  A    B
AK S INT    A    N     AK SO COAST A    N     AK PNHDL    A    N



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 08 - 14 2015

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    B     OREGON      A    B     NRN CALIF   A    B
SRN CALIF   A    N     IDAHO       N    B     NEVADA      A    B
W MONTANA   N    B     E MONTANA   B    N     WYOMING     B    B
UTAH        N    N     ARIZONA     A    A     COLORADO    B    N
NEW MEXICO  N    A     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    B    A     KANSAS      B    A     OKLAHOMA    N    A
N TEXAS     A    N     S TEXAS     A    N     W TEXAS     A    A
MINNESOTA   B    A     IOWA        B    A     MISSOURI    N    A
ARKANSAS    A    A     LOUISIANA   A    A     WISCONSIN   B    A
ILLINOIS    N    A     MISSISSIPPI A    A     MICHIGAN    N    A
INDIANA     A    A     OHIO        A    A     KENTUCKY    A    A
TENNESSEE   A    A     ALABAMA     A    A     NEW YORK    A    A
VERMONT     A    A     NEW HAMP    A    A     MAINE       A    A
MASS        A    A     CONN        A    A     RHODE IS    A    A
PENN        A    A     NEW JERSEY  A    A     W VIRGINIA  A    A
MARYLAND    A    A     DELAWARE    A    A     VIRGINIA    A    A
N CAROLINA  A    A     S CAROLINA  A    A     GEORGIA     A    A
FL PNHDL    A    A     FL PENIN    A    A     AK N SLOPE  A    A
AK ALEUTIAN A    A     AK WESTERN  A    A     AK INT BSN  A    A
AK S INT    A    A     AK SO COAST A    A     AK PNHDL    A    A

                           LEGEND
TEMPS WITH RESPECT TO NORMAL     PCPN WITH RESPECT TO MEDIAN
A - ABOVE   N  - NEAR NORMAL     A - ABOVE   N - NEAR MEDIAN
B - BELOW                        B - BELOW

THE FORECAST CLASSES REPRESENT AVERAGES FOR EACH STATE. NORMAL
VALUES - WHICH MAY VARY WIDELY ACROSS SOME STATES - ARE
AVAILABLE FROM YOUR LOCAL WEATHER SERVICE FORECAST OFFICE.

FOR ADDITIONAL INFORMATION SEE MESSAGE FXUS06 KWBC - ON AWIPS AS
PMDMRD.

$$




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